Iron manganese trioxide

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: as reported in source record

Justification for type of information:

see attachment "Read-across justification-environ assessment-iron oxides" and “Endpoint-specific read-across justification for nano forms of iron oxide, 2021” attached in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: as reported in source record

Description of key information

Applying read-across to nanosizediron(hydr)oxides (see attachment "Read-across justification-environ assessment-iron oxides" and “Endpoint-specific read-across justification for nano forms of iron oxide, 2021” attached in IUCLID section 13), nanosized iron manganese trioxide is not expected to cause chronic toxicity to aquatic invertebrates. Effects of diiron trioxide nanoparticles on the reproduction of Daphnia magna were not observed in a reliable 21-d chronic toxicity study according to OECD 211 up to the highest test concentration of 20 mg/L and an unbounded NOEC of >= 20 mg/L was derived (Nogueira et al., 2015), a concentration that is twofold above the corresponding OECD test limit.

Additional information

A chronic toxicity study was performed by Nogueira et al. (2005) according to OECD 211 to assess the potential effects of nano-Fe2O3 (average particle size 85 × 425 nm) at concentrations of up to 20 mg/L on the reproduction of Daphnia magna, a concentrationthat is 2-fold above the corresponding OECD test limit for chronic toxicity. A significant effect on the reproduction (number of offspring) of Daphnia magna was not observed for Fe2O3 nanoparticles at the applied concentrations of 8.2 to 20.0 mg/L and thus an unbounded 21 d NOEC >= 20 mg/L (nominal) was derived.

Based on read-across to nanosized iron (hydr)oxides (see attachment "Read-across justification-environ assessment-iron oxides" and “Endpoint-specific read-across justification for nano forms of iron oxide, 2021” attached in IUCLID section 13), available data indicate a low potential for chronic toxicity ofnanosized iron manganese trioxideto aquatic invertebrates (see table below).

 

Table: Chronic toxicity of nanosized iron (hydr)oxides to aquatic invertebrates.

Endpoint	Test species	Test results	Test material/form	Reliability: Reference
Long-term toxicity to aquatic invertebrates	Daphnia magna	NOEC (21d): >= 20 mg/L nominal	diiron trioxide / nano	RL2: Nogueira et al., 2015